I. Field of the Invention:
This invention relates generally to a fast-acting switch for conducting large amounts of electrical energy, and more particularly an integrated circuit switching device which, when triggered by a relatively low energy signal, produces a plasma cloud providing a very low impedance discharge path between two high voltage terminals forming a part of the integrated circuit structure.
II. Discussion of the Prior Art:
As is set forth in the Marshall U.S. Pat. No. 4,559,875 entitled "High Energy Switching Circuit for Initiator Means or the Like and Method Therefor", a need exists in the munitions field for a device which will operate reliably to switch very large currents upon triggering thereof. Typically such a device can be used to control the energization of a sapper detonator or to set off a primer charge or a train of a primary charge and one or more booster charges. Given the particular application, it is imperative that such a detonator device have the ability to survive and operate in high G environments. For example, in certain weaponry, it is intended that an explosive shell penetrate through the walls of the fortification before the explosion is detonated. As such, it is essential that the detonation device for the projectile be able to survive the forces encountered during firing, impact and penetration while still reliably detonating the primary explosive charge when triggered or detonated.
In the Hollander U.S. Pat. No. 3,366,055, there is disclosed a semiconductor explosive igniter constructed such that when an electrical current is applied to it, the resistivity of the semiconductor material increases due to heating to a critical point where its resistivity drops precipitously and the semiconductor device disintegrates to release a shock wave sufficient to detonate certain types of high explosives. In accordance with the invention of the Hollander Patent, the critical temperature at which the resistivity drops can be controlled during the manufacture of the semiconductor device by appropriate doping of the silicon material.